Adjustable inductive resistance



(No Model.)

- O. B. SHALLENBERGER.

, ADJUSTABLE INDUWJIVIE: RESISTANCE. No. 380,945. y PatentedA'pr. 1o, 188s.

5mm/WISO@ a; 76, i -l v @51g ifozneflro/ A --UNITED STATES PATENT Ortrcie.9

OLIVERVB. SHALLENBERGER, OF ROCHESTER, ASSIGNOR TOrTHE WESTING- HOUSE ELECTRIC COMPANY, OF PITTSBURG, PENNSYLVANIA.

ADJUSTABLE INDUCTIYE RESISTANCE.

SPECIFICATION forming part o1 Letters Patent No. 380,945, dated Api-i110, 1888. yApplication filed September l, 1987.V Serial No. 248,471. (No model.)

To all whom it may concern: Beit known that I, OLIVER B. SHALLEN- BERGER, a citizen of the United States, residing in Rochester, Beaver county, in the State of Pennsylvania, have invented certain new and useful Improvements in Adjustable Inductive Resistances, of which the following is a specification.

The invention relates to the construction of inductive resistauces employed-for controlling currents in electric circuits.

rlhe object of the invention is to provide a convenient form of adjustable inductive resistance, the value or effect of whichl may be increased as the core is withdrawn from the coils.

The invention consists in applying to a core ofsoft iron oppositely-wound coils of insulated wire, which have equal and opposite effects upon the core when the latter is in its normal position, thus producing no inductive resistance. As the core is withdrawn, however, it is gradually removed from the field of one coil, and thus the value of the other coil greatly increases until its full effect is obtained. The device is further provided with ashort-circuiting switch or cutout, which serves to sh0rtcircuit the coils. when the core is in its normal position.

The invention will be described in its relation to an electric-light system.

In the accompanying drawings, Figure l illustrates the invention, the core being inserted within the two coils; and Fig. 2 shows the core partly removed.

Referring to the drawings, L and Lz represent the main lines of an electric-light circuit, and d a translating device capable of being included in circuit between the lines. For this purpose a conductor, 1, leads from theline LZ to the lamp d, and a conductor, 2, leading from the lamp is connected with one terminal of the coils c'c of aninductive resistance,C. The other terminal of the coils is connected by a conductor, 3,with a Switchpoint, s,.- and the switch, S, applied to this point is connected by a conductor, 4, with the line L. The coils c and c2 of the inductive resistance are oppositely'wound, as

' shown, and may be of equal value or of an equal number of turns. The core cis capable of beingv withdrawnfrom the coils a greater or less distance; but as the coils are placed side by side it will be first withdrawn from thecoil o. It will be seen thus that as it is being Withdrawn from the coil o the inductive resistance established in the circuit will be gradually increased until its maximum is reached, which will be when'the coil c no longer has any appreciable opposing effect.

As it is desired in some instances to remove the resistance of the coils c and c" when no inductive resistance is required,a contact-spring, e', is connected with the conductor 2, and a second contact-spring, e2, is connected byaconductor, 5, with the conductor 3. Vhen, therefore, the core is inserted within both coils, c and c2, a circuitclosing point, e, passes between the springs e and e2, and thus completes the connections of a short-circuit around the coils. As the core is withdrawn from the coils, however, the point or. pin e is withdrawn from the springs, thus interrupting the connections of the short-circuit.

In Fig. l the switch S is shown as being open, and the lamp d is thus out of circuit. In Fig. 2 the switch S is closed, and at the same time theinductive resistance is withdrawn partially from the coil c. By means of this resistance the brilliancy at which the light d will burn may be regulated, thus affording a convenient means for turning down the lamp.

I claim as my invention-fl. The combination, with an incandescent electric lamp and a circuit supplying currents thereto, of an adjustable inductive resistance for turning down the lamp, consisting of magnetizable material and opposing coils of wire wound about the same, both of which are normally included in circuit, substantially as described.

2. The combination, with an incandescent electric lamp, of opposing coils placed in the circuit thereof in series, a core of soft iron applied to said coils and acted upon by currents traversing the same, and means for withdrawing the core a greater or less distance from one of said coils.

3. The combination, with an incandescent electric lamp, of opposing coils placed in the circuit thereof, a core of soft iron applied to said coils and. acted upon by currents traversing the same, means for withdrawing the core a greater or less distance from one of said coils, a short-circuiting device 0r shunt around said coils, and a circuit-closer completing the connections of the same when the core is within both coils.

4. An adjustable inductive resistance consisting of opposing coils connected in series in an electric circuit, a core of soft iron acted upon thereby, and means for withdrawing the core from one of the coils, thereby increasing the inductive resistance, substantially as described.

5. The combination, with two opposing coils and a core of soft iron acted upon thereby, and capable of being withdrawn a greater or less distance from one of the coils while still remaining under the inductive inuence ofthe other coil, of a short-circuiting device about said coils, closed by said core when the 2o latter is in the inductive field of both of said coils.

In testimony whereof have hereunto subscribed my name this 4th day of August, A. D. 1887.

OLIVER B. SHALLENBERGER.

Vitnesses:

NV. D. UPTEGRAFF, L. B. STILLWELL. 

